Hi, I am A. Stevens here to help with your question!
So the first thing to check is to make sure that you have all of the latest updates through Apple Update installed. Can you verify this?
Great, thanks for checking on that. So next thing to check, do you know where to see your saved wireless profiles?
Networks>Advanced>Preferred Wifi Networks
So if you can please delete all of the preferred networks and then re join it to your wifi network as new
OK I will refer to customer service for you
If you are still having problems go to Macintosh HD / Library / Preferences drag the folder SystemConfiguration to the trash. Restart and then connect to your WiFi again and see if there is any improvement. Let me know.